Stressed over dog behaving badly since moving house

There's been a lot of changes in our household recently ... October, November, December I spent a lot of time at my mother's as my dad died and my mum was ill. I took my dog (6 year old rescue cavalier, female neutered, I've had her four years) with me, my mum has a dog too. They used to get on ok, but my dog became very possessive whilst living there and growled at her dog and went for him a few times. She can be a bit possessive anyway, but was always fine with him up to then.

Last year I also separated from my husband and moved with dd. We also have 2 cats.

My dog has always been quite well behaved, but now she climbs up to pinch the cats food, climbs on the table to pinch any food left on plates if I turn my back. She begs for food which she never used to do.

I understand she is probably confused and unsettled and I do not get cross with her, although I do firmly tell her No. We only moved three months ago.

Any ideas how I can make things a little easier for her - and us? I currently feed the cats on the bedroom window sill - previously tried on the dining table (ugh!) and on the cat climbing tree - she found a way of reaching all these places. My kitchen is extremely small and short of work surfaces, I don't like feeding them there.

I have been feeding the cats throughout the day several times, but maybe I need to have set times morning and night and to shut the dog out? The problem with that is one cat is a Siamese and extremely noisy and insistent if he thinks he is hungry and he will pester and pester for food, climbing all over the place, over me, over guests ... I know, it sounds like a mad house!

I'm stressing about it a lot, as I've had a really stressful time and I'm currently written off sick due to anxiety and depression, so it would be nice if I could find a way of dealing with this.

Also, in terms of the cats we had a similar problem which was only helped by really insisting on set meal times. Until that point they just got fed all the time pretty much! It did take a little while, but now they have learnt to eat their food in one go or they have to wait! Changing everyone's food to a good quality food also helped.

I think it can vary! But it did seem to help our dog. The main thing though was really making the cats learn they ate twice a day or the food went. I also shut the dog out whilst they eat. It did take a couple of weeks but really helped.